Downdraft smoke-consuming boiler-furnace.



c. H. HOOK. DOWNDRAFT SMOKE CON'SUMlNGBOILER FURNACE.

Patgnted Aug. 31, 1915.

3 $HEETSSHEET 2.

WITNESS- I N VENTOR. (/1 #0019 WITNESSES:-

C. H. HOOK. DOWNDRAFT SMOKE EONSUMING BOILER FURNACE. APPLICAHON FILED FEH. a. 19:5.

1,151,592. Patented Aug. 31,1915.-

3 SHEETS-SHEET 3.

ATT IVEY.

research use CHARLES HOW RD noon, on rx rrseunen, PENNSYLVANIA.

newline-suit. cartons-consummasemen-summon.

Application filed February 3,1315. Serial No. 5,833.

- To aZI'it may concern Be'it known that I, CHAnLns' HOWARD Hoon, a citizen of the: United Stutes residing at Pittsburgh, in thecounty' of A 1 le- 4 gheny and State of Pennsylvania, have 1ngeneration of steam at a-miniinum consunipa -tionof fuel. i

ments in Downdraft Smoke Consuming vented certain new and useful Improve- Boiler-Furnaces, of \vhich'the following is a specificzitionc I This invention relates to down draft smoke consuming boiler-furnaces and has for its object to providee furnace of such type, in a, manner as hereinafter set forth, with means to provides large water due area in r a compact furnace'hody whereby {1' rapid generstlon of steam is had from a minimum consumption of fuel. 4 v

A further object of the invention is to provide a furnace of the type referred to, in

a manner as hereinafter set forth, with a pair of combustion chambers which nreutiiized for the consumption of the smoke giv-' ingjheat units under such conditions preventing Waste of heat units and facilitating the generation of steam, at the same time overcoming the discharge of Waste smoke containing valuable heat units.

A further object of the im'ention is to prov-idea furnaceof the type referred to, in a manner as here nafter 'set'forth, withan, arrangement of fines positioned tobrenk the water up intoa vust nuniherof small streams "and further positioned whereby the fines will be quickly. attacked by the heat under such conditions" making quick steum and responsive circulation with n 'minlinuni amount of fuel; i I

with menu's in 21' manner as hereinafter set forth, to l'irovide for the quick generation of ste-zun'with e nu nlm'um consumption of fuel.

A furtherobject of the invention isto provide a furnace of" the type referredto,

forth, to ureventthe luicketingof the heat units at the rear of the bridge wall.

in a manner as hereinafter requires." H A further ob ect of the :m-vcntmn is to looking toward the \vardthe front ofthe furnace.

elevation looking towardfhe br'idge. wall medium of a door 2.

,with means in a manner as hereinafter set;

forth, to facilitate the circulation of the heat units with respect to an increasw flue ares under such conditiousln'oviding for a quick- Specificetion oiLetters Potent. Pgfignked Aug; 31, I

Further objects of the inyention are: to

View the invention consists of the novel construction, combination and'arrangement of parts as hereinafter more specifically described and illustrated in the accompanylng drawings, wherein is shown enemhodlment With the foregoing and other iobject s'inofthe invention, but it is. to-lbe understood that changes, variations-and modifications can he resorted to which comes Within the i scope of the claims hereunto appended.-

In the drawings wherein like'referencecharacters denote corresponding parts throughoutthe several views-:-Figure ltisa perspective view of a; sinoke .conslnninggr,

down draft boiler furnace in accordance with this inve ntion, looking toward the front of the furnace. Fig. 2is a similarview.

rear of the furnace. 3 1s a sectional elevationlooking to: Fig. 4 is an u'ith the hack of the furnacereinoved;

n is u perspective View of one of; the fur-- and entrance ;to the latter s-had through the Supported byfthe hose 1 1s a plurulity of rocking combustion v chumber 4,. wlth means in a manner as here nafter grates?) of any, sultzrhle ,eonstr-uctionnnd the said rocking.

'gz'u'tes 3 provide.the bott'omc of the lorveirj The furnace further includessfbodjl tion, which, is mounted .upon the base 1, and u'luch'ronswtsof :1 front unit 5, and n pluruhty of 1nterinedinte'units,-us illustruted sevenin numhemhut' this number can a-rear units hey increased or diminished, and thenumherf of intermediateunits is shown merely by \vsy of exurnpleand said intermediate units I areindicatedby the reference characters 7, e, e. 10, 11,12 and v13. provide a furnace of the type referred to,

The frontunito, ii'ell as tl'ieregir unitfi,

each has a lateral projecting apertured car 14.. The apertured cars 14 are arranged in proximity to the lower ends of said front unit 5 and rear unit 6 and the apertured cars 14 of the front unit 5 are arranged in alinement with the apertured ears 14 of the unit 6 and extending through said alining ears are t e bars 15 for connecting the front unit 5 and rear unit 6 together, and for furthersecuring; in position the intermediate units 7 to 13.

The front unit 5 includes a pair of hollow legs '16, 17, and each of said legs at its lower end has a circular ofiset 18. The legs 16, 17 merge into a hollow arch 19 which forms a. section' of the top of the furnace.

' Below the hollow arch 19 and legs 16, 17,

are connected together by a hollow tube 20 which'forms one section of the top of the primary combustion chamber, the latter is indicated at 21, arranged above the combustion chamber 4, termed. the secondary combustion chamber. The legs 16, 17, are furthermoreconnecte'd by a hollow tube 22,

having the intermediate portion thereof offset as at 23 and the tiibe 22 forms one of the hollow grate bars or one of the sectionsof the bottom of the primary combusj tion chamber. The bar 22 also constitutes onesection of the top ofthe secondaryicombustion chamber 4.

Secured to the front of the front section 5,",

is a plate 24, having a pair of door openings which are closed by the doors 25, 26, and

legs 16, 17, near their lower ends, haveopenter is closed by adoor 30, which providesmeans whereby access can be had to the secondary combustion chamber 4 when 0ccasion so requires. The front section 5, centrally' thereof,..has an upwardly extending circular enlargement 31.

The bottoms of the legs 16, 17, are closed, with the exception, that the real" sides of the ings which commu'nicatewith the openings 32 formed in the front sides of the legs of the int'ermediatcsection 7. The arch 19.01? the front section 5 is closed. with this e.\ception, that centrally thereof at its rear has "an opening 33, which communicates with an opening 34 formed in the front of the arch of the intermediate section 7.

The intermediate sections? 8, 9, 10 and flues 45, 46, 47 and 48. The tubes 40 have 11 are similar in construction, and the descrlption of one will apply to the other and each of the intermediate sections, as desig-. nated, consists of a pair of hollow legs 35, 36, closed at their bottoms with this exceptlon, that the-front side of the lower ends of said legs. are provided with the openings 32- for establishing communication therebetween and the legs 16, 17 and the legs 35,36, are at their rear furthermore provided, with openings 37 for establishing communication between the legs of adjacent intermediate sections. The legs3'5, 36, terminate in a hollow arch 38, which has openings 34and 38 for establishing communication between the arches adjacent sections. The legs 35, and 36, below the arch 38, are connected together by a hollow tube 40, and said tube 40 18 connected Withthe arch 38 by a pair. of spaced vertically disposed tubes 41 and 35 42, removed from the legs 35, 36. The vertically disposed tubes 41, 42, are connected to the legs 35, 36, by short hollow tubes 43. The tube 40 forms a section of-the top of the primary combustion chamber 21; The'gd arch 38, in connection with the tube '40 and the tubes 41 and 42 provide heat fiues 44.

The legs 35, 36, in connection with the arch 38, tubes 41, 42, and tubes 43, form heat their lower surfaces corrugated as at 49. t

The legs 35, 36, below the tube 46, are connected together by a hollow tube 50, having reduced ends and a pair of longitudinally. f

disposed end openings 51 and a longitudinally disposed intermediate opening 52. The latter is of greater length than either of the former.. The tube 50 forms one of the grate bars or a section of the bottom of the 1 primary combustion chamber 21, and the re- 5 duced ends of the tube and openings Q1, 52, provide means fot the passage of hot coals. from the primarycombustion chamber 21 into the secondary combustion chamber 4 to form a bed of livefu'el in said latter chamo ber.

Leading from the lower section of eacn leg 35, 36, and merging into a tube 50, is a tube 53, of any suitable shape preferably of compound curvature or S-shape. The upper ends of the curved tubes preferably are spaced from each other. and said tuhes 53 establish communication between the legs 35, 36, and the tube 50 to provide for the circulation of water across the upper portion of the chamber 4 in-additional to the cir culation of watera t the sides and top of the chamber 4. f

The tubes 50 of the intermediate sections 7 to 11, both inclusive, provide the bottom on I the grate of the primary combustion" chain ber 21, and are disposed preferably in a horifzontal plane and although the preferred cm struction of these tubes50 is illustrated,

' et'it is to be understood the tubes b 136 arranged in curvilinear alinementso as to set up a concave grate, or bottom. The

' tubes 50 also constitute the top of the secondary combustion chamber 4.

The intermediate section 12 has its upper portion constructed similar to that ofthe intermediate sections 7 to 11, with this exi is provided which splits .the'water up in 36, of said section 12 and the tube 40 are oppositely disposed tubes 55, preferably of compound curvature or s-sh'ape.

The upper portion of' the intermediate section 13 is constructed similar to the upper portions, of the intermediate sections 7 to 11, but the intermediatesection 13 is not provided with a tube. 50, andleadingfrom thelegs 35, 36, from the intermediate' portion 13 to the tube 40 are oppositely disposed tubes 56, preferably of compound curvature or S-shape.

a I. .5 i a The rear section 6 18 of the "same construc tion as the front section 5, with this eircep tion, that it' is provided wlth a single-door o pcning, closed by a door, 57 whereby access can be had tothe rear of the entrance.

Anoutlet oi isprovided in the rear section, and inlets 59 are formed in the ,intermediate sections.

By setting up the water tubes in -a man ner as stated a vast number of Water ways small streams and the tubes whichprovide such .water ways can be quickly attacked, by'the heat thereby-facilitatingthe rapid" generation of steam.

The fire is built in the primary comliustion el1amber.'2]., and owing, to the'arraiige'- meat of the draft is' obvious that the smoke will be drawn down into the second As the live coals lall through the opearings in the grate of the ary combustion chamber 4.

primary c(m1l;ustion 'chau'iber 21' and onto the grate 3 ol thesecondary combustion chamber 4, abedoif' incandescent fuel Will be :mcumulateil, and as .the smoke is drawn through the lire in the primary mmbustion' chamber and into the secondary combustion chamber, the incandescent fuel \Vlll consume the heat giving units carried by the smoke instead of allowing" of waste of smoke thcrelrvmaking quick' steamwith a ninimum amountoi' r'uel. -.lhe heatlflues provide for quickcirculation oi the heat and as the water tubes form the walls of'such fines it is obvious that there could notbe other?" wlse than a quick generatioirof steam. The

Water not only circulates through the tubes forming the heat tlues, but also through the I heat fines. I

3' setting up thefurnace, at the rear of low grate bars providing pas bridge wall, the grate of the primary combustion chamber and through the tip of the secondary combustion chamber.

As the intermediate sections 7 to 12,-w1th their vertically disposed tubes 41 and l9) are spaced from the front section 5 and rear section 6, it is obvious that nothing is'set up to retard the passage of the heat through the the ridge wall 54, in the manner as illustrated, the formation of pockets are over- I i come and retarded.

What I claim is:

1. A down draft smolie consuming boiler furnace-comprising an upper and a lower fuel combustion chamber each having. side Walls formed-with passagesfor the circ'ulw' tion 'of water, said upper ch mber provided the circulation or? the heat is not v "as with a bridge wall at'and said lower chamber open at the rear thereof, said upper chamber hating its bottom consisting of hollow grate bars providing passages for water circulation opening into the water passages i; the side walls of said chamber,

said bars forming the top of said lower ;.chamber, and means communicating ,with

and extending from each of the water pas,-

sages in the side walls of and opening into the hollow grate bars to provide passages for? the circulation of water.

1' 2'. A downdraft smoke consuming boiler furnace comprising ail-upper and alowe'r 'fuel combustion chamber each having side walls formed with passages for'the' circulation of Water, said upper chamber provided with a bridge wall at said lower chamber open at the rear thereof, said upper cham- ..ber having-it's bottom coi'zs'isting'of hollow grate bars providing passages for water circulation, openinlg'intothe side Water pas-I sages in the walls'of said chamber, said bars forming the tl'oppf said lower chamber, and inwardly pro ect ng curved tubes communicating withand extending from each of the water passages in the side walls of'and opening at their upper ends into said grate bars to provide passages forthe circulation of WVMIBL, i

fuel combustion -chamber?=-each "having side walls formed-with passages for the circulation of water, said upper chamber provided with a bridge wall at and said lower chamber open at the rear thereof,- said upper chamber having its l'aottoin circulation opening into th forming the topbf said lower chamber-arid Im-l1ir1g'n1'eai1s-to pro-ville vertically disposed openings independenb'ofthe' water passages tor-med in said grate bars, said openings uteri) sages its -inthe side walls of saidcliainbei sald'bars i'inedby holges for water;

- i v V 3. A down draft smoke consuming boiler furnace comprising an'u'p-per and slower providingfmeans for the passage oflive coals from the upper to the lower chamber to form a bedof'live fuel in said lower chamber to consume the smoke as it passes down through the grate bars.

with a bridge \all at and'said lower chamber a passages openings providing means for the passage open at the rear thereof, said upper chamber having its bottom formed of hollow grate bars providing passages for water circulation opening into the side walls of said chamber,

said bars forming the top of said lower chamber and means to provide vertically disposed openings independent of said water formed in said grate bars, said of live coals from the upper tothe lower chamber to form a bed of live fuel in said lower chamber to consume the smoke as it passesdown through the grate bars, and means -COIIlI11llI1lC21tlng with from each of the water passages of saidside walls of and opening into the grate bars to provide passages for the circulation of v water.

bottom formed of hollow 5,;i down draft smoke consuming boiler,

furnace comprising an upper and a lower fuel combustion chamber each having side walls formed with passages for the circulation of water said upper chamber provided with a bridge wall at and saidlower chamber open at the rear thereof, said upper chamberhaving its bottom formed of ho llow grate bars providing passages for water circulation opening into the side walls of said chamber; said bars forming the top of said lower chamber and having means to provide vertically disposed openings independent of the water passages formed in said grate bars, said openings permitting the passage of live coals from the upper to the lower chamber to form a bed of live fuel in said lower chamber to consume the smoke as it passes down through the grate bars, and

inwardly projecting curved tubes (LOITIIIIHIIIJ eating with and extending from each of the side walls of and opening into the water passages of grate bars to provide passages for the circulation of water.

6. A down draft smoke consuming boiler furnace comprising an upper and alower fuel combustion chamber each having side walls formed with passages for the circulation of water, said upper-chamber having its grate bars providing passagesfor the water circulation opening into the side walls of said chamber, said grate bars forming the top of lower chamber and having means to provide vertically disposed openings independent of the water passages formed in said grate bars,

.iiiunicating with and and extending said openings permitting the passage of live coals from the upper to the lower chamber to provide a bed of live fuel in said lower chamber to consume the smoke it passes down through the grate bars.

7. A down'tdraft smoke consuming boiler furnace comprising an upper and a-lower fuel combustion chamber each having side wallsformed with passages for the circulationof water, said upper chamber having a bed of live fuel in said lower chamber to consuinef the smoke as it passes down through the gratebars, and means comextendingfrom the water passages of the sidewalls of and opening into the grate bars forming top of said lower chamber to provide for the circulation of water.

S.- A down draft smoke consuming boiler. furnace comprising an upper and a lower fuel combustion chamber each having side walls formed with passages for the circulation of water.,said upper chamber having the'bottom thereof formed of hollow grate bars. providing passages for water vcirculatioii-opeiiing into the'passagesjof the side walls ofsaid'chamber, said grate bars forming thetop of said lower chamber and havng means to provide vertically disposed ,openings independent of the water passages formed in said grate bars. said openings permitting of the passage of live coals from the upper to the lower chamber to provide a bed of live fuel in said lower chamber to consume the smoke as it passes down through the grate bars, and' inwardly projecting curved tubes communicating with and extending fromeach of the water passages of the side walls of the opening into the grate bars forming the top of said lower chamber to provide for the circulation ofwater.'

9. A down draft smoke consuming boiler furnace comprising an upper and a lowerfuel combustion chamber each havingvside walls providedvwith passages fol-the circulation of ater, means to provide passages K for the "cii'culationof waterover said upper chamber and fol-further forming a central longitudinal heat flue and outer superposed longitudinal heat fines at each side of said central flue and communicating with each other, tubes for water circulationopening into said walls providing grate barsforthe upper chamber and the top of said'lower'. chamber, a bridge wall at the rear of-:-"said bars and opening into said means at the rear 1 530?? the bridge well and providing for the circulation of Water rearvvardly of the bridge Willi. l

"'10. A down draft smoke cons'mning boiler 'Lftu'nace comprising'anupper and at lower fuel combustion 'charnber each having side Walls provided withpassages'forthe circu=-.

lation of 'te1',-inean s to provide'passages rmthe circulationof water over said upper chamber and for fnrtherprovidings cen trail. longitudinal heat fine and outer superposed longitudinal heat fines at'each side of com'nn nicating with said central flue, .tubes :tor water circulation opening into 7 Said side Walls andfproviding grate bars for the upper chamber and the top of said) lo v'erchamber, abridge wall at theiear of said upperchamber, and tubes coinniunr' eating with and extending fromeach oilthc side Walls of seid lower chamber below the I topthereof and opening into said means at the'rear of saidbridge wall and providing for the circulation of Water: rearxrerdly of the l)l1(l well, said grate bars 'l avlng i :1 1 means to provide vertically disposed openmgs independent of the :water passeges formed in sin grate hers, said open ngs'permitting for the passage oflive coals from the upper vto the lower cl an iber to forin a bed of live fuel'ih the lower chsmli er to consuine the smoke as it passes down through the grate'bars.

1111i down draft smoke cor smiling boiler ;lurnace comprising an upper and e iowcs fuel combustion chamber each having side- 40 Wells prbvided With'passages for the circulation of Water, means to provide passages vfor the circulation of Water over said upper chamber and for further providing a central'lcngitudinal heat fine and outer super- 5 -posechlongi'tndinal heat fines at each side oil and communicating with said central line,

tubes for Water circulation, opening into said side Wells and, providing gratebars for the upper'chamber and the top of said lower w chamber, a bridge Wall at the rear of s'sid :ipper chamber, tribes communicating with and extending from each. of t'lie side Walls of said lclwer chamber below the top thereof rind open ng into said means at the r'e'i r of said bridge Well and providing fortlie cir- H I I I v the passages iormed by said means com- 5 and means communicating witlif and extend=' ignites grate bars for the upper chember and 'fursaid lower chamber. v

" 12. A downdraft smokeconsuming boiler furnace comprising an upper and a iower fuel combustion chamber each having side Walls formed with passages for the circulartion of water, means forming passages for the circiilation' of water over said upper chamber and further formingfiues for the pits-sage ()fllQiiii, said fines communicating with, the rear of the said lower chamber and the passages formed by said means commumeeting. with said Walls, tubes forming passages for the circulation of Water and open- I ing into said side walls and providing grate 4 bars for the upper chamber and further providing the top of said lower chamber; and 35,. means communicating with 'and extending from ench'oi thesaid Walls of and opening intotbe grate bars forming the top'of said lovfer chamber to provide for the circulation of Water in the upper portion of the lower chemhei:

A down draftsmoke consuming boiler furnace comprising an upper and a lower 7 fuel combustion chamber each having side walls formed with passages vfor the circulationbf Water, means forming passages for "the circulation of Water over said upper chamber and further forming fines for the passage oi. heat, said flues communicating with th'ercur oi'the said lower chamber and the passages formed by said means communicating with said \vallsituhes forming passages" for the circulation of water and opening into said-side walls and providing the top of'siid lower chamber, and inwardly projecting curved tubes cormnunicating with and extending from each of the side walls of andxopeningg into the grate bg rs forming tlie top of lower chamber to provide for the circulationof Water in the upper por- "tion of the lower chamber. 7 r f l-l. A. down draft smoke consuming boiler furnace comprising an upper and fa lower 'fuel combustion chamber each having side walls formed with passages for the circulation of wateifmeans forming'passages for the circulzition of water over Said iipper chamber 1nd further forming lines for the passage of heat, saidfiues communicnting with the res-1' of the said lower chamber and municatin with said walls;- tnbes'formin passiigesior the circulation of water an opening int'o said side Wells and providing ther providing the top of said lpwer chainber, end. means communicating Withand extending from eachof the said nllsof and I ope'nin into the grate'bars"torming' the top of sci lower charnoer provide for the Circulation of water 1n the upper portion of said lower chamber, said grate bars.hav-' ing means to provide vertically disposed openings independent of thewater passages "formed in said grate bars and said openings permitting for the passage of live coals from the upper to the lower chamber to form In the latter a bed of live fuel to consume the smoke as it passes down through the grate bars. 7 p

'15. A down draft smoke consuming boiler furnace comprising an upper and a lower fuel combustion chamber each having side I walls formed with passages for-the circulation of water, means forming passages for the circulation of water over said upper chamber and further forming fines for the passage of heat, said fines communicatin with the rear of the said lower chamber an the passages formed by said means communicating with said walls, tubedforming "passages for the circulation of water and opening into said side walls and providing grate bars for the upper chamber and further providing thetop of said lower chamher, and inwardly projecting curved tubes communicating with and extending from each of the side walls of and opening into the grate bars forming the top of said lower chamber to provide for the circ'ulation of water, said grate bars having means to pro- I vide vertically disposed openings independent of the water passages. formed in said grate bars and said openings'permitting for the passage of live coals from the upper to the lower chamber to form in the latter a .bed of live fuel to consume the smoke as it passes down through the grate bars.

16'. A down draft smoke c onsumingboiler furnace comprising an upper and a lower combustion chamber each having its top and sides formed with communicating passages for the circulation of water, the top of said lower chamber constituting the bottom of said upper chamber and further providing gratebars for said upper chamber, said grate bars having vertical openingsfor'the passage of live'coals from said upper chamei' to said lower chamber to form a bed of live' fuel. to consume the smoke as it passes down through-the grate bars, and inwardly projectingtubes communicating with each of the sides of said lower chamber and opening into the grate bars and providing means for the circulation of water. v 17. A down draft smoke consuming boiler furnace comprising an upper and a lower combustion chamber each having its top and sides formed withcommunicating passages for the circulation of water, the top of said lowerchamber constituting the bottom of said upper chamber and further providing grate barsv for said upper chamber, said grate bars having means to provide vertical openlngs for the passage of live coals fromsaid upper chamber to said lower chamber 'to form a bed of live fuel to consume the smoke I as it passes down through the. grate bars, inwardly projecting tubes, communlcatmg with each'of the sides of said lower chamber and opening into the grate bars and proriding means for circulating of water, and means connected with thetop of said upper chamber to provide communicating passages for the circulation of water and further providingfiues for the circulation of heat, said fines communicating with said lower chamber. I

181 A down draft smoke consuming boiler furnace comprising an upper and a lower combustion chamber each having its top and sides-formed with communicating passages for the circulation of water, the top of saidlower chamber constituting the' bottom of I said upper chamber. and further providing 7 grate bars for said upper chamber, said grate bars having means to provide vertical openings for the passage of live coals from said upper chamber-to said lower chamber.

to form a bed of live fuel to consume the smoke as it passes down through the grate bars, inwardly projecting tubes communicating with each of the sides of said lower chamber. and opening into the grate bars. providing means for the circulation of water, means connected with the top of said upper chamber to provide communicating passages for thev circulation-of water and further providing fines for the circulation of'heat, said fluescommunicating with said lower chamber, a hollow bridge wall at the. end ofsaid upper chamber and opening to the sides of said lower chamber, and upwardly extending tubes arranged at the rearv of said bridge wall and opening into and projecting from the sides of said lower chamber and opening into said grate bars and extending to and communicating with said means and providing passages for the.

circulation of water.

19. A'down draft smoke'con suming boiler furnace comp1'ising an upper-and a lower combustion chamber, water circulating tubes forming the grate of the uppe f'cha-mher I and the top of the.lower chambe thesides of said lower'chamber being formedwith water passages, and pipes arranged in said e of the upper chamber lower chamber and opening into said tubes y combustion c-hamber forming the grate of the top of the said lower chamber being formed with water passages, and curved pipes arranged in said lower chamber and openiiig into said. tubes and intothc water said lower chamber to provide for water circulation tlu'ough the upper portion of said lower chamber. l

22. A down draft smoke consuming boiler furnace comprising combustion chamber, water circulating tubes forming the grate of the upper chamber and the top of the lower chamber the sides of said lower chamber being formed with water passages, and pipes of compound curvature arranged in sand lower chamber and opening into said tubes and into the water passages oi the sides of said lower chamocr to proride for water circulation through the upper portion of said lower chamber.

:23.".\ down draft smoke consuming boiler furnace comprising an upper and a lower combustion chamber adapted to contain a body of live fuch' water circulating tubes 'l'ormiug the grate and bottom of the upper z-hambcraml the top of the'lower chamber, the sides or said lower chamber being l ra-med of water passages tubes opem pipes of compound curvature riding for passages of the sides of,

an upper and a lower into which said arranged in said lower chamber and open mg at their upper ends into said tubes and at their lower ends into the Water passages of'the sides of said lower chamber for prowater circulation through the upper portion of said lower chamber, a

hollow bridge wall communicating with said" and arranged at/ the rear of water passages said upper chamber, and water eirculatlng pipes of compound curvature arranged'at the rear of said bridge wall.

2% A down draft smoke consun'iing boiler furnace comprising an upper and a lower comlmstion chamber body of live fuel, water circulating tubes Forming the bottom and the grate of the upper chamber and the top of the lower chamber, the sides of said chambers being formed of water passages, said tubes opening into said water passages, pipes arranged in said lower chamber and open ng at their upper ends into said tubes and at their lower ends into the water passages formed in the sides of said lower chamber to provide for water circulation through the upper portion oi said lower chamber, ahollow bridge wall arranged at the rear of said upper chamber and opening into said water-passages, and pipes fol-water circulation con'mmnicating with said water passages and arranged at the rear of said bridge wall.

ln testimony whereof I ailix my signature in presence of t\\o witnesses. 7

CHARLES HOlVARD HOOK. ivitnesscs 1 B. M. BouAN,

V. D. RANKIX.

adapted to contain a' 

